July 17, 2008—Midshipman fish, such as the one seen above, are sometimes called canaries of the sea, because males hum songs to attract mates.

A new study of these musical fish reveals that the brain circuit controlling their ballads is similar to the neural wiring that allows birds, frogs, and other animals to vocalize. (Read the full story.)

The last time all of these creatures shared a common ancestor was more than 400 million years ago, when the evolutionary line that led to toadfish split from the line that eventually led to land vertebrates.

"This one circuit in the brain is very ancient, and it's been retained throughout the course of evolution by all animals that vocalize," said study leader Andrew Bass of Cornell University. He and colleagues present their findings in this week's issue of the journal Science.